1. Field of the Invention
The present invention relates to a switching mode power supply, and more particularly, to a switching mode power supply for reducing power consumption in a no load mode.
2. Description of the Related Art
As a switching mode power supply, a switching mode type switching mode power supply (SMPS) capable of satisfying requirements such as having a small size and high efficiency is widely used. This switching mode power supply has been used in an adapter, which is an external power supply of a notebook computer, a liquid crystal display (LCD) monitor, a stereo, or the like.
An operation state of the adapter is divided into a no load mode in which a load is connected to an alternating current (AC) power source but is not connected to an output and an on mode in which the load is connected to both of the AC power source and the output. Recently, power consumption in the no load mode as well as in the on mode has been strictly regulated for the saving of energy.
As a method of reducing power consumption, the switching mode power supply according to the related art has used a burst method of repeating a process in which a switching operation is performed for a predetermined time and the switching operation is stopped for a predetermined time through feedback at the time of a light load.
However, the switching mode power supply using the burst method according to the related art has difficulty in responding to a power consumption restriction level in a no load mode, which may continuously be high.